The present invention relates to an aerodynamic fairing of the rear portion of an aircraft pylon which is also referred to as an “aft pylon fairing” or APF.
Such an aerodynamic fairing is known in particular from the document U.S. Pat. No. 4,712,750. In this document, the aerodynamic fairing is in the form of a casing which comprises two lateral panels which are assembled together by means of frames or transverse inner reinforcement ribs which are spaced apart from each other along the longitudinal axis of the fairing, and a thermal protection floor which is fixed, on the one hand, to the lateral panels and, on the other hand, to the transverse inner ribs with which the floor is in contact.
In a position for use, such a fairing is subjected to very high temperatures which originate from the engine unit of the aircraft. These temperatures bring about deformations as a result of thermal expansions of the fairing, thus disrupting the aerodynamic qualities thereof. In particular, the thermal protection floor is subjected to a primary flow of the turbo engine at high temperature (in the order of 600° C.) while the lateral panels are subjected to a secondary flow of the turbo engine at a relatively low temperature (in the order of 150° C.) in relation to that of the primary flow. These temperature differences bring about significant thermomechanical stresses on the casing.